Cummins
Cummins fault code
SPN 647 / FMI 11
Cummins Fault Code 389: Fan Clutch Circuit Error
389 on Cummins engines means: Fan Clutch Circuit Error. The failure mode (FMI 11) is “root cause not known”.
Lamp: Yellow
Engine may continue to run, but must be repaired the same day.
Code details
- Manufacturer
- Cummins
- Applies to
- Cummins QS-series electronic engines
- Fault code
- 389
- J1939 SPN
- 647
- FMI
- 11 — Root cause not known
- J1587 PID / SID
- S033
- Engine models
- QSB, QSC, QSL9
What to do next
- Read active and inactive codes with the OEM service tool and note the occurrence count.
- FMI 11 tells the shop the type of failure to test for: root cause not known.
- Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.
Get this code diagnosed
Send one request and nearby diesel shops and mobile mechanics can quote the repair.
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Related fault codes
Source: Cummins "Diagnostic Fault Codes For Cummins Engines", publication 80-1044 Rev 5/2013, page 11. See also OBD-II codes.